nginx服务器和我们平常用的linux操作系统（centos，ubuntu）有什么区别吗？

Question

nginx服务器和我们平常用的linux操作系统（centos，ubuntu）有什么区别吗？能不能打个比喻？

Answer 1

Metaphor:
Operating system: a platform
nginx: an application

Answer 2

nginx is a program that provides web services or reverse proxy services. Those two are operating systems and are not the same category

Answer 3

Debian-based Ubuntu, Redhat-based CentOS, these are GNU/Linux distributions.
Nginx is a cross-platform web server software that can run on Unix-like systems (such as Linux/*BSD/macOS, etc.) It can also run on Windows, or even run on Android/iOS devices after cross compilation.